Narrative:

Preflight done on M20J per usual routine in light rain prior to departing. Began takeoff roll. At or shortly after rotation; noticed brisk air flow in cockpit. Using 'anr' headset; so did not notice any unusual sound. Glancing around; however; saw that baggage door had popped open. Because of concern about lined up aircraft behind me possibly rolling; elected to continue takeoff; made standard left pattern; and landed uneventfully to secure damaged door and remove wet insulation from empennage. Inspection of aircraft revealed no significant damage other than to door. M20J baggage door is piano hinged at top and closes down snugly and flush to outer skin of fuselage. Latch when moved to flush; 'closed' position activates fore and aft pins that secure lower portion of door to door frame in fuselage. Latch is usually not locked in case of requirement for emergency extrication. Baggage door of incident aircraft late model (original equipment in 1995 M20J mse) with interior latch release safetied by cotter pin. Baggage door of incident aircraft subsequently removed by maintenance facility. Exterior door skins and top of frame adjacent to piano hinge deemed too damaged for economical repair. Upon cycling intact and evidently undamaged lock mechanism; failure mode idented by a&P in which fore and aft pins did not move to engaged; 'closed' position despite latch being in appropriate 'closed' position. Suspect incident resulted from this fault in the latch; since best recollection of pilot is that preflight was unremarkable and latch was in closed; flush position. Popped baggage doors have been previously reported in mooney aircraft and several modifications have been made to the latching mechanism in attempts to correct this problem. Apparently; there is opportunity for further improvement. This is a safety hazard. Although the open door did not adversely affect the aircraft's handling; it was certainly a distraction to the pilot in a critical phase of flight. Callback conversation with reporter revealed the following information: reporter stated that he is about 99% certain that the door was closed and latched prior to flight. In his case the aircraft was perfectly flyable but he understands that there has been at least one event that resulted in an accident due to pilot distraction. He commented that he was distracted but that he merely continued flying the aircraft with a known problem. The door was badly battered in the wind and is being replaced.

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Original NASA ASRS Text

Title: A MOONEY'S BAGGAGE DOOR POPPED OPEN DURING TKOF AFTER THE FORE AND AFT PINS DID NOT MOVE TO ENGAGE. THE LATCH WAS IN THE CLOSED POSITION AND THE DOOR APPEARED CLOSED DURING PREFLT.

Narrative: PREFLT DONE ON M20J PER USUAL ROUTINE IN LIGHT RAIN PRIOR TO DEPARTING. BEGAN TKOF ROLL. AT OR SHORTLY AFTER ROTATION; NOTICED BRISK AIR FLOW IN COCKPIT. USING 'ANR' HEADSET; SO DID NOT NOTICE ANY UNUSUAL SOUND. GLANCING AROUND; HOWEVER; SAW THAT BAGGAGE DOOR HAD POPPED OPEN. BECAUSE OF CONCERN ABOUT LINED UP ACFT BEHIND ME POSSIBLY ROLLING; ELECTED TO CONTINUE TKOF; MADE STANDARD L PATTERN; AND LANDED UNEVENTFULLY TO SECURE DAMAGED DOOR AND REMOVE WET INSULATION FROM EMPENNAGE. INSPECTION OF ACFT REVEALED NO SIGNIFICANT DAMAGE OTHER THAN TO DOOR. M20J BAGGAGE DOOR IS PIANO HINGED AT TOP AND CLOSES DOWN SNUGLY AND FLUSH TO OUTER SKIN OF FUSELAGE. LATCH WHEN MOVED TO FLUSH; 'CLOSED' POS ACTIVATES FORE AND AFT PINS THAT SECURE LOWER PORTION OF DOOR TO DOOR FRAME IN FUSELAGE. LATCH IS USUALLY NOT LOCKED IN CASE OF REQUIREMENT FOR EMER EXTRICATION. BAGGAGE DOOR OF INCIDENT ACFT LATE MODEL (ORIGINAL EQUIP IN 1995 M20J MSE) WITH INTERIOR LATCH RELEASE SAFETIED BY COTTER PIN. BAGGAGE DOOR OF INCIDENT ACFT SUBSEQUENTLY REMOVED BY MAINT FACILITY. EXTERIOR DOOR SKINS AND TOP OF FRAME ADJACENT TO PIANO HINGE DEEMED TOO DAMAGED FOR ECONOMICAL REPAIR. UPON CYCLING INTACT AND EVIDENTLY UNDAMAGED LOCK MECHANISM; FAILURE MODE IDENTED BY A&P IN WHICH FORE AND AFT PINS DID NOT MOVE TO ENGAGED; 'CLOSED' POS DESPITE LATCH BEING IN APPROPRIATE 'CLOSED' POS. SUSPECT INCIDENT RESULTED FROM THIS FAULT IN THE LATCH; SINCE BEST RECOLLECTION OF PLT IS THAT PREFLT WAS UNREMARKABLE AND LATCH WAS IN CLOSED; FLUSH POS. POPPED BAGGAGE DOORS HAVE BEEN PREVIOUSLY RPTED IN MOONEY ACFT AND SEVERAL MODIFICATIONS HAVE BEEN MADE TO THE LATCHING MECHANISM IN ATTEMPTS TO CORRECT THIS PROB. APPARENTLY; THERE IS OPPORTUNITY FOR FURTHER IMPROVEMENT. THIS IS A SAFETY HAZARD. ALTHOUGH THE OPEN DOOR DID NOT ADVERSELY AFFECT THE ACFT'S HANDLING; IT WAS CERTAINLY A DISTR TO THE PLT IN A CRITICAL PHASE OF FLT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THAT HE IS ABOUT 99% CERTAIN THAT THE DOOR WAS CLOSED AND LATCHED PRIOR TO FLT. IN HIS CASE THE ACFT WAS PERFECTLY FLYABLE BUT HE UNDERSTANDS THAT THERE HAS BEEN AT LEAST ONE EVENT THAT RESULTED IN AN ACCIDENT DUE TO PILOT DISTRACTION. HE COMMENTED THAT HE WAS DISTRACTED BUT THAT HE MERELY CONTINUED FLYING THE ACFT WITH A KNOWN PROBLEM. THE DOOR WAS BADLY BATTERED IN THE WIND AND IS BEING REPLACED.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.